Femtosecond laser induced emission enhancement in Rhodamine6G

Significant enhancement in the peak intensity of fluorescent emission has been observed in dye solution of Rhodamine6G in Methyl Methacrylate on irradiation with femtosecond laser pulses. Detailed studies have been carried out by varying the parameters like exposure time, dye concentration and pump power density to determine the optimum conditions for maximum fluorescent emission enhancement. Up to 30% increase in peak intensity has been found to occur with significant increase in fluorescent quantum yield. Fourier Transform Infra Red spectra recorded before and after irradiation reveal that xanthene ring in Rhodamine6G molecule gets deformed and a new intermediate state of the dye is formed before its gets deteriorated as the exposure time is increased well above the optimum value.